* uprobes: memory leak in enable/disable loop
@ 2016-08-15 20:58 Brenden Blanco
2016-08-16 14:13 ` Oleg Nesterov
0 siblings, 1 reply; 12+ messages in thread
From: Brenden Blanco @ 2016-08-15 20:58 UTC (permalink / raw)
To: linux-kernel
Cc: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Alexei Starovoitov, Oleg Nesterov
Hi folks,
I think I have come across a memory leak in uprobes, which is fairly easy to
reproduce.
Using a repeated use of a single uprobe, I am able to run my system out of
memory, resulting in system failures and a need to reboot the box. When I
first became aware of the failure, I was able to narrow down the first
userspace-visible failure to -ENOMEM being returned from
kernel/events/uprobes.c:uprobe_write_opcode(), though I can't say whether that
is the actual cause of the leak or just a victim. With the below reproduction
steps, hopefully someone smarter than me can understand the problem and propose
a solution, which I would be happy to test.
So far, I have reproduced the issue on kernels 4.4 and 4.8-rc2. I've tried on
distributions from Ubuntu as well as Arch Linux. Continue reading for a rough
log of the steps to reproduce.
Thanks,
Brenden
----------------------------------------
root@localhost# uname -r
4.8.0-040800rc2-generic
root@localhost# cd /sys/kernel/debug/tracing
root@localhost# echo "p:uprobes/libc_so_6 /lib/x86_64-linux-gnu/libc.so.6:0x0000000000086560" > uprobe_events
root@localhost# # number of iterations before failure depends on the amount of memory in your system
root@localhost# for i in {1..48}; do echo 1 > events/uprobes/libc_so_6/enable; echo 0 > events/uprobes/libc_so_6/enable; done
root@localhost# dmesg
[ 2182.439038] ------------[ cut here ]------------
[ 2182.439042] WARNING: CPU: 6 PID: 4763 at /home/kernel/COD/linux/mm/page_counter.c:26 page_counter_uncharge+0x1d/0x30
[ 2182.439043] Modules linked in: fuse binfmt_misc snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep ppdev snd_pcm parport_pc snd_timer sg virtio_balloon virtio_console acpi_cpufreq parport serio_raw i2c_piix4 snd soundcore tpm_tis intel_powerclamp tpm_tis_core intel_rapl_perf evdev squashfs tpm loop ib_iser rdma_cm iw_cm ib_cm ib_core configfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi autofs4 ext4 crc16 jbd2 fscrypto mbcache btrfs dm_mod raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod ata_generic 8139too crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel qxl aesni_intel aes_x86_64 lrw ttm virtio_pci ehci_pci uhci_hcd drm_kms_helper ehci_hcd ata_piix
[ 2182.439067] gf128mul psmouse virtio_ring glue_helper libata ablk_helper 8139cp scsi_mod cryptd mii usbcore usb_common floppy virtio drm button
[ 2182.439074] CPU: 6 PID: 4763 Comm: bash Not tainted 4.8.0-040800rc2-generic #201608142332
[ 2182.439074] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20160701_074356-anatol 04/01/2014
[ 2182.439075] 0000000000000286 00000000d2708db2 ffffffff9ad3de94 0000000000000000
[ 2182.439076] 0000000000000000 ffffffff9aa7f4ee ffff8be0e749e8c0 000000000000001f
[ 2182.439077] ffff8be0e749e800 000000000000001f ffff8be0f4647bb0 ffff8be0e71860c0
[ 2182.439078] Call Trace:
[ 2182.439081] [<ffffffff9ad3de94>] ? dump_stack+0x5c/0x78
[ 2182.439083] [<ffffffff9aa7f4ee>] ? __warn+0xbe/0xe0
[ 2182.439084] [<ffffffff9abff52d>] ? page_counter_uncharge+0x1d/0x30
[ 2182.439085] [<ffffffff9ac01512>] ? drain_stock.isra.30+0x32/0xa0
[ 2182.439086] [<ffffffff9ac023f1>] ? try_charge+0x5f1/0x6b0
[ 2182.439087] [<ffffffff9abe610b>] ? alloc_pages_vma+0xbb/0x240
[ 2182.439088] [<ffffffff9ac06157>] ? mem_cgroup_try_charge+0x67/0x1b0
[ 2182.439090] [<ffffffff9ab8156c>] ? uprobe_write_opcode+0x25c/0x5e0
[ 2182.439091] [<ffffffff9ab81965>] ? install_breakpoint.isra.21.part.22+0x55/0x70
[ 2182.439092] [<ffffffff9ab81d0d>] ? register_for_each_vma+0x36d/0x420
[ 2182.439092] [<ffffffff9ab8201e>] ? uprobe_register+0x16e/0x290
[ 2182.439094] [<ffffffff9ab65aef>] ? probe_event_enable+0xef/0x350
[ 2182.439096] [<ffffffff9ab51cdc>] ? __ftrace_event_enable_disable+0x5c/0x1e0
[ 2182.439097] [<ffffffff9ab52645>] ? event_enable_write+0x95/0xe0
[ 2182.439098] [<ffffffff9ac0ebc3>] ? __vfs_write+0x33/0x160
[ 2182.439101] [<ffffffff9ac2e49e>] ? __fd_install+0x2e/0xe0
[ 2182.439102] [<ffffffff9ac2e313>] ? __alloc_fd+0x43/0x170
[ 2182.439104] [<ffffffff9acacf78>] ? security_file_permission+0x38/0xb0
[ 2182.439105] [<ffffffff9ac0f2c0>] ? vfs_write+0xb0/0x190
[ 2182.439106] [<ffffffff9ac10692>] ? SyS_write+0x52/0xc0
[ 2182.439107] [<ffffffff9ac2ea65>] ? SyS_dup2+0x95/0x100
[ 2182.439109] [<ffffffff9b01d8b6>] ? entry_SYSCALL_64_fastpath+0x1e/0xa8
[ 2182.439110] ---[ end trace 320efb00be7bb830 ]---
After this, continued toggling of the uprobe will eventually fail.
root@localhost# for i in {1..100}; do echo 1 > events/uprobes/libc_so_6/enable; [[ $? -ne 0 ]] && break; echo 0 > events/uprobes/libc_so_6/enable; done
-bash: echo: write error: Cannot allocate memory
After running the uprobes out of memory, oom-killer started to pick off system processes:
[ 97.334378] acpid invoked oom-killer: gfp_mask=0x24000c0(GFP_KERNEL), order=0, oom_score_adj=0
[ 97.334379] acpid cpuset=/ mems_allowed=0
[ 97.334383] CPU: 4 PID: 4179 Comm: acpid Tainted: G W 4.8.0-040800rc2-generic #201608142332
[ 97.334384] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20160701_074356-anatol 04/01/2014
[ 97.334385] 0000000000000286 000000006b30ae78 ffffffffa673de94 ffff9522a946be08
[ 97.334387] ffff9522a9464640 ffffffffa660b716 ffff9522a946bd78 ffff9522a9453cc0
[ 97.334388] 0000000000030080 ffffffffa658c0e6 0007ffffffffffff ffff9522a9464640
[ 97.334390] Call Trace:
[ 97.334395] [<ffffffffa673de94>] ? dump_stack+0x5c/0x78
[ 97.334397] [<ffffffffa660b716>] ? dump_header+0x59/0x1dc
[ 97.334398] [<ffffffffa658c0e6>] ? find_lock_task_mm+0x36/0x80
[ 97.334400] [<ffffffffa658ccb2>] ? oom_kill_process+0x222/0x3e0
[ 97.334402] [<ffffffffa6602910>] ? mem_cgroup_iter+0x100/0x2e0
[ 97.334403] [<ffffffffa6604c2d>] ? mem_cgroup_out_of_memory+0x28d/0x2d0
[ 97.334405] [<ffffffffa660575e>] ? mem_cgroup_oom_synchronize+0x32e/0x340
[ 97.334406] [<ffffffffa6600ab0>] ? memory_high_write+0xd0/0xd0
[ 97.334408] [<ffffffffa658d30d>] ? pagefault_out_of_memory+0x4d/0xc0
[ 97.334410] [<ffffffffa6a1ec88>] ? async_page_fault+0x28/0x30
[ 97.334411] Task in /system.slice/acpid.service killed as a result of limit of /system.slice/acpid.service
[ 97.334414] memory: usage 18446744073709551276kB, limit 9007199254740988kB, failcnt 121
[ 97.334414] memory+swap: usage 0kB, limit 9007199254740988kB, failcnt 0
[ 97.334415] kmem: usage 52kB, limit 9007199254740988kB, failcnt 0
[ 97.334415] Memory cgroup stats for /system.slice/acpid.service: cache:0KB rss:0KB rss_huge:0KB mapped_file:0KB dirty:0KB writeback:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
[ 97.334422] [ pid ] uid tgid total_vm rss nr_ptes nr_pmds swapents oom_score_adj name
[ 97.334637] [ 4179] 0 4179 1100 287 7 3 37 0 acpid
[ 97.334651] Memory cgroup out of memory: Kill process 4179 (acpid) score 0 or sacrifice child
[ 97.334695] Killed process 4179 (acpid) total-vm:4400kB, anon-rss:0kB, file-rss:1148kB, shmem-rss:0kB
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-15 20:58 uprobes: memory leak in enable/disable loop Brenden Blanco
@ 2016-08-16 14:13 ` Oleg Nesterov
2016-08-16 14:25 ` Oleg Nesterov
0 siblings, 1 reply; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-16 14:13 UTC (permalink / raw)
To: Brenden Blanco, Johannes Weiner, Michal Hocko, Vladimir Davydov
Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Alexander Shishkin, Alexei Starovoitov
On 08/15, Brenden Blanco wrote:
>
> Hi folks,
>
> I think I have come across a memory leak in uprobes, which is fairly easy to
> reproduce.
At first glance this looks as a problem in memcg, add CC's...
put_page(old_page) looks properly balanced, and I assume we do not need
the additional "uncharge", we can rely on __page_cache_release().
And I do not see any leak if I try to reproduce with CONFIG_MEMCG=n.
> Using a repeated use of a single uprobe, I am able to run my system out of
> memory, resulting in system failures and a need to reboot the box. When I
> first became aware of the failure, I was able to narrow down the first
> userspace-visible failure to -ENOMEM being returned from
> kernel/events/uprobes.c:uprobe_write_opcode(), though I can't say whether that
> is the actual cause of the leak or just a victim. With the below reproduction
> steps, hopefully someone smarter than me can understand the problem and propose
> a solution, which I would be happy to test.
>
> So far, I have reproduced the issue on kernels 4.4 and 4.8-rc2. I've tried on
> distributions from Ubuntu as well as Arch Linux. Continue reading for a rough
> log of the steps to reproduce.
>
> Thanks,
> Brenden
>
> ----------------------------------------
>
> root@localhost# uname -r
> 4.8.0-040800rc2-generic
> root@localhost# cd /sys/kernel/debug/tracing
> root@localhost# echo "p:uprobes/libc_so_6 /lib/x86_64-linux-gnu/libc.so.6:0x0000000000086560" > uprobe_events
> root@localhost# # number of iterations before failure depends on the amount of memory in your system
> root@localhost# for i in {1..48}; do echo 1 > events/uprobes/libc_so_6/enable; echo 0 > events/uprobes/libc_so_6/enable; done
>
> root@localhost# dmesg
> [ 2182.439038] ------------[ cut here ]------------
> [ 2182.439042] WARNING: CPU: 6 PID: 4763 at /home/kernel/COD/linux/mm/page_counter.c:26 page_counter_uncharge+0x1d/0x30
> [ 2182.439043] Modules linked in: fuse binfmt_misc snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep ppdev snd_pcm parport_pc snd_timer sg virtio_balloon virtio_console acpi_cpufreq parport serio_raw i2c_piix4 snd soundcore tpm_tis intel_powerclamp tpm_tis_core intel_rapl_perf evdev squashfs tpm loop ib_iser rdma_cm iw_cm ib_cm ib_core configfs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi autofs4 ext4 crc16 jbd2 fscrypto mbcache btrfs dm_mod raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sd_mod ata_generic 8139too crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel qxl aesni_intel aes_x86_64 lrw ttm virtio_pci ehci_pci uhci_hcd drm_kms_helper ehci_hcd ata_piix
> [ 2182.439067] gf128mul psmouse virtio_ring glue_helper libata ablk_helper 8139cp scsi_mod cryptd mii usbcore usb_common floppy virtio drm button
> [ 2182.439074] CPU: 6 PID: 4763 Comm: bash Not tainted 4.8.0-040800rc2-generic #201608142332
> [ 2182.439074] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20160701_074356-anatol 04/01/2014
> [ 2182.439075] 0000000000000286 00000000d2708db2 ffffffff9ad3de94 0000000000000000
> [ 2182.439076] 0000000000000000 ffffffff9aa7f4ee ffff8be0e749e8c0 000000000000001f
> [ 2182.439077] ffff8be0e749e800 000000000000001f ffff8be0f4647bb0 ffff8be0e71860c0
> [ 2182.439078] Call Trace:
> [ 2182.439081] [<ffffffff9ad3de94>] ? dump_stack+0x5c/0x78
> [ 2182.439083] [<ffffffff9aa7f4ee>] ? __warn+0xbe/0xe0
> [ 2182.439084] [<ffffffff9abff52d>] ? page_counter_uncharge+0x1d/0x30
> [ 2182.439085] [<ffffffff9ac01512>] ? drain_stock.isra.30+0x32/0xa0
> [ 2182.439086] [<ffffffff9ac023f1>] ? try_charge+0x5f1/0x6b0
> [ 2182.439087] [<ffffffff9abe610b>] ? alloc_pages_vma+0xbb/0x240
> [ 2182.439088] [<ffffffff9ac06157>] ? mem_cgroup_try_charge+0x67/0x1b0
> [ 2182.439090] [<ffffffff9ab8156c>] ? uprobe_write_opcode+0x25c/0x5e0
> [ 2182.439091] [<ffffffff9ab81965>] ? install_breakpoint.isra.21.part.22+0x55/0x70
> [ 2182.439092] [<ffffffff9ab81d0d>] ? register_for_each_vma+0x36d/0x420
> [ 2182.439092] [<ffffffff9ab8201e>] ? uprobe_register+0x16e/0x290
> [ 2182.439094] [<ffffffff9ab65aef>] ? probe_event_enable+0xef/0x350
> [ 2182.439096] [<ffffffff9ab51cdc>] ? __ftrace_event_enable_disable+0x5c/0x1e0
> [ 2182.439097] [<ffffffff9ab52645>] ? event_enable_write+0x95/0xe0
> [ 2182.439098] [<ffffffff9ac0ebc3>] ? __vfs_write+0x33/0x160
> [ 2182.439101] [<ffffffff9ac2e49e>] ? __fd_install+0x2e/0xe0
> [ 2182.439102] [<ffffffff9ac2e313>] ? __alloc_fd+0x43/0x170
> [ 2182.439104] [<ffffffff9acacf78>] ? security_file_permission+0x38/0xb0
> [ 2182.439105] [<ffffffff9ac0f2c0>] ? vfs_write+0xb0/0x190
> [ 2182.439106] [<ffffffff9ac10692>] ? SyS_write+0x52/0xc0
> [ 2182.439107] [<ffffffff9ac2ea65>] ? SyS_dup2+0x95/0x100
> [ 2182.439109] [<ffffffff9b01d8b6>] ? entry_SYSCALL_64_fastpath+0x1e/0xa8
> [ 2182.439110] ---[ end trace 320efb00be7bb830 ]---
>
> After this, continued toggling of the uprobe will eventually fail.
>
> root@localhost# for i in {1..100}; do echo 1 > events/uprobes/libc_so_6/enable; [[ $? -ne 0 ]] && break; echo 0 > events/uprobes/libc_so_6/enable; done
> -bash: echo: write error: Cannot allocate memory
>
> After running the uprobes out of memory, oom-killer started to pick off system processes:
>
> [ 97.334378] acpid invoked oom-killer: gfp_mask=0x24000c0(GFP_KERNEL), order=0, oom_score_adj=0
> [ 97.334379] acpid cpuset=/ mems_allowed=0
> [ 97.334383] CPU: 4 PID: 4179 Comm: acpid Tainted: G W 4.8.0-040800rc2-generic #201608142332
> [ 97.334384] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20160701_074356-anatol 04/01/2014
> [ 97.334385] 0000000000000286 000000006b30ae78 ffffffffa673de94 ffff9522a946be08
> [ 97.334387] ffff9522a9464640 ffffffffa660b716 ffff9522a946bd78 ffff9522a9453cc0
> [ 97.334388] 0000000000030080 ffffffffa658c0e6 0007ffffffffffff ffff9522a9464640
> [ 97.334390] Call Trace:
> [ 97.334395] [<ffffffffa673de94>] ? dump_stack+0x5c/0x78
> [ 97.334397] [<ffffffffa660b716>] ? dump_header+0x59/0x1dc
> [ 97.334398] [<ffffffffa658c0e6>] ? find_lock_task_mm+0x36/0x80
> [ 97.334400] [<ffffffffa658ccb2>] ? oom_kill_process+0x222/0x3e0
> [ 97.334402] [<ffffffffa6602910>] ? mem_cgroup_iter+0x100/0x2e0
> [ 97.334403] [<ffffffffa6604c2d>] ? mem_cgroup_out_of_memory+0x28d/0x2d0
> [ 97.334405] [<ffffffffa660575e>] ? mem_cgroup_oom_synchronize+0x32e/0x340
> [ 97.334406] [<ffffffffa6600ab0>] ? memory_high_write+0xd0/0xd0
> [ 97.334408] [<ffffffffa658d30d>] ? pagefault_out_of_memory+0x4d/0xc0
> [ 97.334410] [<ffffffffa6a1ec88>] ? async_page_fault+0x28/0x30
> [ 97.334411] Task in /system.slice/acpid.service killed as a result of limit of /system.slice/acpid.service
> [ 97.334414] memory: usage 18446744073709551276kB, limit 9007199254740988kB, failcnt 121
> [ 97.334414] memory+swap: usage 0kB, limit 9007199254740988kB, failcnt 0
> [ 97.334415] kmem: usage 52kB, limit 9007199254740988kB, failcnt 0
> [ 97.334415] Memory cgroup stats for /system.slice/acpid.service: cache:0KB rss:0KB rss_huge:0KB mapped_file:0KB dirty:0KB writeback:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
> [ 97.334422] [ pid ] uid tgid total_vm rss nr_ptes nr_pmds swapents oom_score_adj name
> [ 97.334637] [ 4179] 0 4179 1100 287 7 3 37 0 acpid
> [ 97.334651] Memory cgroup out of memory: Kill process 4179 (acpid) score 0 or sacrifice child
> [ 97.334695] Killed process 4179 (acpid) total-vm:4400kB, anon-rss:0kB, file-rss:1148kB, shmem-rss:0kB
>
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-16 14:13 ` Oleg Nesterov
@ 2016-08-16 14:25 ` Oleg Nesterov
2016-08-16 14:34 ` Oleg Nesterov
2016-08-16 14:37 ` Michal Hocko
0 siblings, 2 replies; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-16 14:25 UTC (permalink / raw)
To: Brenden Blanco, Johannes Weiner, Michal Hocko, Vladimir Davydov
Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Alexander Shishkin, Alexei Starovoitov
On 08/16, Oleg Nesterov wrote:
>
> On 08/15, Brenden Blanco wrote:
> >
> > Hi folks,
> >
> > I think I have come across a memory leak in uprobes, which is fairly easy to
> > reproduce.
>
> At first glance this looks as a problem in memcg, add CC's...
>
> put_page(old_page) looks properly balanced, and I assume we do not need
> the additional "uncharge", we can rely on __page_cache_release().
>
> And I do not see any leak if I try to reproduce with CONFIG_MEMCG=n.
Heh. it seems that mem_cgroup_*() logic was always wrong in __replace_page().
Could you try the patch below?
Oleg.
---
--- x/kernel/events/uprobes.c
+++ x/kernel/events/uprobes.c
@@ -200,7 +200,8 @@ static int __replace_page(struct vm_area
err = 0;
unlock:
- mem_cgroup_cancel_charge(kpage, memcg, false);
+ if (err)
+ mem_cgroup_cancel_charge(kpage, memcg, false);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
unlock_page(page);
return err;
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-16 14:25 ` Oleg Nesterov
@ 2016-08-16 14:34 ` Oleg Nesterov
2016-08-16 16:55 ` Brenden Blanco
2016-08-16 17:36 ` uprobes: memory leak in enable/disable loop Johannes Weiner
2016-08-16 14:37 ` Michal Hocko
1 sibling, 2 replies; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-16 14:34 UTC (permalink / raw)
To: Brenden Blanco, Johannes Weiner, Michal Hocko, Vladimir Davydov
Cc: linux-kernel, Peter Zijlstra, Ingo Molnar,
Arnaldo Carvalho de Melo, Alexander Shishkin, Alexei Starovoitov
On 08/16, Oleg Nesterov wrote:
>
> On 08/16, Oleg Nesterov wrote:
> >
> > On 08/15, Brenden Blanco wrote:
> > >
> > > Hi folks,
> > >
> > > I think I have come across a memory leak in uprobes, which is fairly easy to
> > > reproduce.
> >
> > At first glance this looks as a problem in memcg, add CC's...
> >
> > put_page(old_page) looks properly balanced, and I assume we do not need
> > the additional "uncharge", we can rely on __page_cache_release().
> >
> > And I do not see any leak if I try to reproduce with CONFIG_MEMCG=n.
>
> Heh. it seems that mem_cgroup_*() logic was always wrong in __replace_page().
Yes, it seems this was broken by 00501b53 "mm: memcontrol: rewrite charge API".
> Could you try the patch below?
Please see v2 below. We don't need "cancel_charge" under "unlock:" at all.
Johannes, could you review?
Oleg.
---
--- x/kernel/events/uprobes.c
+++ x/kernel/events/uprobes.c
@@ -172,8 +172,10 @@ static int __replace_page(struct vm_area
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
ptep = page_check_address(page, mm, addr, &ptl, 0);
- if (!ptep)
+ if (!ptep) {
+ mem_cgroup_cancel_charge(kpage, memcg, false);
goto unlock;
+ }
get_page(kpage);
page_add_new_anon_rmap(kpage, vma, addr, false);
@@ -200,7 +202,6 @@ static int __replace_page(struct vm_area
err = 0;
unlock:
- mem_cgroup_cancel_charge(kpage, memcg, false);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
unlock_page(page);
return err;
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-16 14:25 ` Oleg Nesterov
2016-08-16 14:34 ` Oleg Nesterov
@ 2016-08-16 14:37 ` Michal Hocko
1 sibling, 0 replies; 12+ messages in thread
From: Michal Hocko @ 2016-08-16 14:37 UTC (permalink / raw)
To: Oleg Nesterov
Cc: Brenden Blanco, Johannes Weiner, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Alexei Starovoitov
On Tue 16-08-16 16:25:12, Oleg Nesterov wrote:
> On 08/16, Oleg Nesterov wrote:
> >
> > On 08/15, Brenden Blanco wrote:
> > >
> > > Hi folks,
> > >
> > > I think I have come across a memory leak in uprobes, which is fairly easy to
> > > reproduce.
> >
> > At first glance this looks as a problem in memcg, add CC's...
> >
> > put_page(old_page) looks properly balanced, and I assume we do not need
> > the additional "uncharge", we can rely on __page_cache_release().
> >
> > And I do not see any leak if I try to reproduce with CONFIG_MEMCG=n.
>
> Heh. it seems that mem_cgroup_*() logic was always wrong in __replace_page().
Yes this seems broken since 00501b531c47 ("mm: memcontrol: rewrite
charge API")
> Could you try the patch below?
The patch looks good to me. Thanks!
> Oleg.
> ---
>
> --- x/kernel/events/uprobes.c
> +++ x/kernel/events/uprobes.c
> @@ -200,7 +200,8 @@ static int __replace_page(struct vm_area
>
> err = 0;
> unlock:
> - mem_cgroup_cancel_charge(kpage, memcg, false);
> + if (err)
> + mem_cgroup_cancel_charge(kpage, memcg, false);
> mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
> unlock_page(page);
> return err;
--
Michal Hocko
SUSE Labs
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-16 14:34 ` Oleg Nesterov
@ 2016-08-16 16:55 ` Brenden Blanco
2016-08-17 15:36 ` [PATCH 0/2] " Oleg Nesterov
2016-08-16 17:36 ` uprobes: memory leak in enable/disable loop Johannes Weiner
1 sibling, 1 reply; 12+ messages in thread
From: Brenden Blanco @ 2016-08-16 16:55 UTC (permalink / raw)
To: Oleg Nesterov
Cc: Johannes Weiner, Michal Hocko, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Alexei Starovoitov
On Tue, Aug 16, 2016 at 04:34:08PM +0200, Oleg Nesterov wrote:
> On 08/16, Oleg Nesterov wrote:
> >
> > On 08/16, Oleg Nesterov wrote:
> > >
> > > On 08/15, Brenden Blanco wrote:
> > > >
> > > > Hi folks,
> > > >
> > > > I think I have come across a memory leak in uprobes, which is fairly easy to
> > > > reproduce.
> > >
> > > At first glance this looks as a problem in memcg, add CC's...
> > >
> > > put_page(old_page) looks properly balanced, and I assume we do not need
> > > the additional "uncharge", we can rely on __page_cache_release().
> > >
> > > And I do not see any leak if I try to reproduce with CONFIG_MEMCG=n.
> >
> > Heh. it seems that mem_cgroup_*() logic was always wrong in __replace_page().
>
> Yes, it seems this was broken by 00501b53 "mm: memcontrol: rewrite charge API".
>
> > Could you try the patch below?
>
> Please see v2 below. We don't need "cancel_charge" under "unlock:" at all.
>
> Johannes, could you review?
>
> Oleg.
> ---
> --- x/kernel/events/uprobes.c
> +++ x/kernel/events/uprobes.c
> @@ -172,8 +172,10 @@ static int __replace_page(struct vm_area
> mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
> err = -EAGAIN;
> ptep = page_check_address(page, mm, addr, &ptl, 0);
> - if (!ptep)
> + if (!ptep) {
> + mem_cgroup_cancel_charge(kpage, memcg, false);
> goto unlock;
> + }
>
> get_page(kpage);
> page_add_new_anon_rmap(kpage, vma, addr, false);
> @@ -200,7 +202,6 @@ static int __replace_page(struct vm_area
>
> err = 0;
> unlock:
> - mem_cgroup_cancel_charge(kpage, memcg, false);
> mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
> unlock_page(page);
> return err;
>
This passes my tests, thanks!
Please note that I applied this to 4.4.15+ubuntu-patches kernel, since that
was what I had most handy, therefore I had to adjust the patch to remove the
unavailable 'compound' bool parameter in 4.4 kernels.
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: uprobes: memory leak in enable/disable loop
2016-08-16 14:34 ` Oleg Nesterov
2016-08-16 16:55 ` Brenden Blanco
@ 2016-08-16 17:36 ` Johannes Weiner
1 sibling, 0 replies; 12+ messages in thread
From: Johannes Weiner @ 2016-08-16 17:36 UTC (permalink / raw)
To: Oleg Nesterov
Cc: Brenden Blanco, Michal Hocko, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo,
Alexander Shishkin, Alexei Starovoitov
On Tue, Aug 16, 2016 at 04:34:08PM +0200, Oleg Nesterov wrote:
> @@ -172,8 +172,10 @@ static int __replace_page(struct vm_area
> mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
> err = -EAGAIN;
> ptep = page_check_address(page, mm, addr, &ptl, 0);
> - if (!ptep)
> + if (!ptep) {
> + mem_cgroup_cancel_charge(kpage, memcg, false);
> goto unlock;
> + }
>
> get_page(kpage);
> page_add_new_anon_rmap(kpage, vma, addr, false);
> @@ -200,7 +202,6 @@ static int __replace_page(struct vm_area
>
> err = 0;
> unlock:
> - mem_cgroup_cancel_charge(kpage, memcg, false);
Ouch. I must have mistaken this for an exclusive error path.
The patch looks good, thank you.
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Fixes: 00501b531c47 ("mm: memcontrol: rewrite charge API")
Cc: stable@vger.kernel.org # 3.17+
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 0/2] uprobes: memory leak in enable/disable loop
2016-08-16 16:55 ` Brenden Blanco
@ 2016-08-17 15:36 ` Oleg Nesterov
2016-08-17 15:36 ` [PATCH 1/2] uprobes: fix the memcg accounting Oleg Nesterov
2016-08-17 15:37 ` [PATCH 2/2] uprobes: rename the "struct page *" args of __replace_page() Oleg Nesterov
0 siblings, 2 replies; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-17 15:36 UTC (permalink / raw)
To: Brenden Blanco, Ingo Molnar
Cc: Johannes Weiner, Michal Hocko, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Arnaldo Carvalho de Melo, Alexander Shishkin,
Alexei Starovoitov
On 08/16, Brenden Blanco wrote:
>
> This passes my tests, thanks!
Great, thanks Brenden!
> Please note that I applied this to 4.4.15+ubuntu-patches kernel, since that
> was what I had most handy, therefore I had to adjust the patch to remove the
> unavailable 'compound' bool parameter in 4.4 kernels.
Yes, sure, this is correct.
Ingo, could you take this fix? IMO 1/2 is 4.8 and -stable matterial.
As for 2/2 it is purely cosmetic but I simply can't resist, I wanted
to make this change every time I had to look at __replace_page().
Oleg.
kernel/events/uprobes.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 1/2] uprobes: fix the memcg accounting
2016-08-17 15:36 ` [PATCH 0/2] " Oleg Nesterov
@ 2016-08-17 15:36 ` Oleg Nesterov
2016-08-18 8:07 ` [tip:perf/urgent] uprobes: Fix " tip-bot for Oleg Nesterov
2016-08-17 15:37 ` [PATCH 2/2] uprobes: rename the "struct page *" args of __replace_page() Oleg Nesterov
1 sibling, 1 reply; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-17 15:36 UTC (permalink / raw)
To: Brenden Blanco, Ingo Molnar
Cc: Johannes Weiner, Michal Hocko, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Arnaldo Carvalho de Melo, Alexander Shishkin,
Alexei Starovoitov
__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path,
it should only do this if page_check_address() fails.
This means that every enable/disable leads to unbalanced mem_cgroup_uncharge()
from put_page(old_page), it is trivial to underflow the page_counter->count
and trigger OOM.
Reported-and-tested-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Michal Hocko <mhocko@kernel.org>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Fixes: 00501b531c47 ("mm: memcontrol: rewrite charge API")
Cc: stable@vger.kernel.org # 3.17+
---
kernel/events/uprobes.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index b7a525a..8c50276 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -172,8 +172,10 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
ptep = page_check_address(page, mm, addr, &ptl, 0);
- if (!ptep)
+ if (!ptep) {
+ mem_cgroup_cancel_charge(kpage, memcg, false);
goto unlock;
+ }
get_page(kpage);
page_add_new_anon_rmap(kpage, vma, addr, false);
@@ -200,7 +202,6 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
err = 0;
unlock:
- mem_cgroup_cancel_charge(kpage, memcg, false);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
unlock_page(page);
return err;
--
2.5.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [PATCH 2/2] uprobes: rename the "struct page *" args of __replace_page()
2016-08-17 15:36 ` [PATCH 0/2] " Oleg Nesterov
2016-08-17 15:36 ` [PATCH 1/2] uprobes: fix the memcg accounting Oleg Nesterov
@ 2016-08-17 15:37 ` Oleg Nesterov
2016-08-18 10:49 ` [tip:perf/core] uprobes: Rename " tip-bot for Oleg Nesterov
1 sibling, 1 reply; 12+ messages in thread
From: Oleg Nesterov @ 2016-08-17 15:37 UTC (permalink / raw)
To: Brenden Blanco, Ingo Molnar
Cc: Johannes Weiner, Michal Hocko, Vladimir Davydov, linux-kernel,
Peter Zijlstra, Arnaldo Carvalho de Melo, Alexander Shishkin,
Alexei Starovoitov
Purely cosmetic, no changes in the compiled code.
Perhaps it is just me but I can hardly read __replace_page() because I can't
distinguish "page" from "kpage" and because I need to look at the caller to
to ensure that, say, kpage is really the new page and the code is correct.
Rename them to old_page and new_page, this matches the caller.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
---
kernel/events/uprobes.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 8c50276..d4129bb 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -150,7 +150,7 @@ static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
* Returns 0 on success, -EFAULT on failure.
*/
static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
- struct page *page, struct page *kpage)
+ struct page *old_page, struct page *new_page)
{
struct mm_struct *mm = vma->vm_mm;
spinlock_t *ptl;
@@ -161,49 +161,49 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
const unsigned long mmun_end = addr + PAGE_SIZE;
struct mem_cgroup *memcg;
- err = mem_cgroup_try_charge(kpage, vma->vm_mm, GFP_KERNEL, &memcg,
+ err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL, &memcg,
false);
if (err)
return err;
/* For try_to_free_swap() and munlock_vma_page() below */
- lock_page(page);
+ lock_page(old_page);
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
- ptep = page_check_address(page, mm, addr, &ptl, 0);
+ ptep = page_check_address(old_page, mm, addr, &ptl, 0);
if (!ptep) {
- mem_cgroup_cancel_charge(kpage, memcg, false);
+ mem_cgroup_cancel_charge(new_page, memcg, false);
goto unlock;
}
- get_page(kpage);
- page_add_new_anon_rmap(kpage, vma, addr, false);
- mem_cgroup_commit_charge(kpage, memcg, false, false);
- lru_cache_add_active_or_unevictable(kpage, vma);
+ get_page(new_page);
+ page_add_new_anon_rmap(new_page, vma, addr, false);
+ mem_cgroup_commit_charge(new_page, memcg, false, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
- if (!PageAnon(page)) {
- dec_mm_counter(mm, mm_counter_file(page));
+ if (!PageAnon(old_page)) {
+ dec_mm_counter(mm, mm_counter_file(old_page));
inc_mm_counter(mm, MM_ANONPAGES);
}
flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush_notify(vma, addr, ptep);
- set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot));
+ set_pte_at_notify(mm, addr, ptep, mk_pte(new_page, vma->vm_page_prot));
- page_remove_rmap(page, false);
- if (!page_mapped(page))
- try_to_free_swap(page);
+ page_remove_rmap(old_page, false);
+ if (!page_mapped(old_page))
+ try_to_free_swap(old_page);
pte_unmap_unlock(ptep, ptl);
if (vma->vm_flags & VM_LOCKED)
- munlock_vma_page(page);
- put_page(page);
+ munlock_vma_page(old_page);
+ put_page(old_page);
err = 0;
unlock:
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
- unlock_page(page);
+ unlock_page(old_page);
return err;
}
--
2.5.0
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [tip:perf/urgent] uprobes: Fix the memcg accounting
2016-08-17 15:36 ` [PATCH 1/2] uprobes: fix the memcg accounting Oleg Nesterov
@ 2016-08-18 8:07 ` tip-bot for Oleg Nesterov
0 siblings, 0 replies; 12+ messages in thread
From: tip-bot for Oleg Nesterov @ 2016-08-18 8:07 UTC (permalink / raw)
To: linux-tip-commits
Cc: hpa, vdavydov, oleg, mingo, alexander.shishkin, torvalds,
bblanco, tglx, acme, jolsa, acme, mhocko, hannes,
alexei.starovoitov, peterz, linux-kernel
Commit-ID: 6c4687cc17a788a6dd8de3e27dbeabb7cbd3e066
Gitweb: http://git.kernel.org/tip/6c4687cc17a788a6dd8de3e27dbeabb7cbd3e066
Author: Oleg Nesterov <oleg@redhat.com>
AuthorDate: Wed, 17 Aug 2016 17:36:29 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 18 Aug 2016 10:03:26 +0200
uprobes: Fix the memcg accounting
__replace_page() wronlgy calls mem_cgroup_cancel_charge() in "success" path,
it should only do this if page_check_address() fails.
This means that every enable/disable leads to unbalanced mem_cgroup_uncharge()
from put_page(old_page), it is trivial to underflow the page_counter->count
and trigger OOM.
Reported-and-tested-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: stable@vger.kernel.org # 3.17+
Fixes: 00501b531c47 ("mm: memcontrol: rewrite charge API")
Link: http://lkml.kernel.org/r/20160817153629.GB29724@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/events/uprobes.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index b7a525a..8c50276 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -172,8 +172,10 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
ptep = page_check_address(page, mm, addr, &ptl, 0);
- if (!ptep)
+ if (!ptep) {
+ mem_cgroup_cancel_charge(kpage, memcg, false);
goto unlock;
+ }
get_page(kpage);
page_add_new_anon_rmap(kpage, vma, addr, false);
@@ -200,7 +202,6 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
err = 0;
unlock:
- mem_cgroup_cancel_charge(kpage, memcg, false);
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
unlock_page(page);
return err;
^ permalink raw reply related [flat|nested] 12+ messages in thread
* [tip:perf/core] uprobes: Rename the "struct page *" args of __replace_page()
2016-08-17 15:37 ` [PATCH 2/2] uprobes: rename the "struct page *" args of __replace_page() Oleg Nesterov
@ 2016-08-18 10:49 ` tip-bot for Oleg Nesterov
0 siblings, 0 replies; 12+ messages in thread
From: tip-bot for Oleg Nesterov @ 2016-08-18 10:49 UTC (permalink / raw)
To: linux-tip-commits
Cc: bblanco, mingo, torvalds, alexei.starovoitov, acme,
alexander.shishkin, oleg, acme, tglx, hpa, linux-kernel,
vdavydov, mhocko, jolsa, peterz, hannes
Commit-ID: bdfaa2eecd5f6ca0cb5cff2bc7a974a15a2fd21b
Gitweb: http://git.kernel.org/tip/bdfaa2eecd5f6ca0cb5cff2bc7a974a15a2fd21b
Author: Oleg Nesterov <oleg@redhat.com>
AuthorDate: Wed, 17 Aug 2016 17:37:04 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Thu, 18 Aug 2016 10:03:50 +0200
uprobes: Rename the "struct page *" args of __replace_page()
Purely cosmetic, no changes in the compiled code.
Perhaps it is just me but I can hardly read __replace_page() because I can't
distinguish "page" from "kpage" and because I need to look at the caller to
to ensure that, say, kpage is really the new page and the code is correct.
Rename them to old_page and new_page, this matches the caller.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Brenden Blanco <bblanco@plumgrid.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Link: http://lkml.kernel.org/r/20160817153704.GC29724@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
kernel/events/uprobes.c | 36 ++++++++++++++++++------------------
1 file changed, 18 insertions(+), 18 deletions(-)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 8c50276..d4129bb 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -150,7 +150,7 @@ static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
* Returns 0 on success, -EFAULT on failure.
*/
static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
- struct page *page, struct page *kpage)
+ struct page *old_page, struct page *new_page)
{
struct mm_struct *mm = vma->vm_mm;
spinlock_t *ptl;
@@ -161,49 +161,49 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
const unsigned long mmun_end = addr + PAGE_SIZE;
struct mem_cgroup *memcg;
- err = mem_cgroup_try_charge(kpage, vma->vm_mm, GFP_KERNEL, &memcg,
+ err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL, &memcg,
false);
if (err)
return err;
/* For try_to_free_swap() and munlock_vma_page() below */
- lock_page(page);
+ lock_page(old_page);
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
- ptep = page_check_address(page, mm, addr, &ptl, 0);
+ ptep = page_check_address(old_page, mm, addr, &ptl, 0);
if (!ptep) {
- mem_cgroup_cancel_charge(kpage, memcg, false);
+ mem_cgroup_cancel_charge(new_page, memcg, false);
goto unlock;
}
- get_page(kpage);
- page_add_new_anon_rmap(kpage, vma, addr, false);
- mem_cgroup_commit_charge(kpage, memcg, false, false);
- lru_cache_add_active_or_unevictable(kpage, vma);
+ get_page(new_page);
+ page_add_new_anon_rmap(new_page, vma, addr, false);
+ mem_cgroup_commit_charge(new_page, memcg, false, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
- if (!PageAnon(page)) {
- dec_mm_counter(mm, mm_counter_file(page));
+ if (!PageAnon(old_page)) {
+ dec_mm_counter(mm, mm_counter_file(old_page));
inc_mm_counter(mm, MM_ANONPAGES);
}
flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush_notify(vma, addr, ptep);
- set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot));
+ set_pte_at_notify(mm, addr, ptep, mk_pte(new_page, vma->vm_page_prot));
- page_remove_rmap(page, false);
- if (!page_mapped(page))
- try_to_free_swap(page);
+ page_remove_rmap(old_page, false);
+ if (!page_mapped(old_page))
+ try_to_free_swap(old_page);
pte_unmap_unlock(ptep, ptl);
if (vma->vm_flags & VM_LOCKED)
- munlock_vma_page(page);
- put_page(page);
+ munlock_vma_page(old_page);
+ put_page(old_page);
err = 0;
unlock:
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
- unlock_page(page);
+ unlock_page(old_page);
return err;
}
^ permalink raw reply related [flat|nested] 12+ messages in thread
end of thread, other threads:[~2016-08-18 10:50 UTC | newest]
Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-08-15 20:58 uprobes: memory leak in enable/disable loop Brenden Blanco
2016-08-16 14:13 ` Oleg Nesterov
2016-08-16 14:25 ` Oleg Nesterov
2016-08-16 14:34 ` Oleg Nesterov
2016-08-16 16:55 ` Brenden Blanco
2016-08-17 15:36 ` [PATCH 0/2] " Oleg Nesterov
2016-08-17 15:36 ` [PATCH 1/2] uprobes: fix the memcg accounting Oleg Nesterov
2016-08-18 8:07 ` [tip:perf/urgent] uprobes: Fix " tip-bot for Oleg Nesterov
2016-08-17 15:37 ` [PATCH 2/2] uprobes: rename the "struct page *" args of __replace_page() Oleg Nesterov
2016-08-18 10:49 ` [tip:perf/core] uprobes: Rename " tip-bot for Oleg Nesterov
2016-08-16 17:36 ` uprobes: memory leak in enable/disable loop Johannes Weiner
2016-08-16 14:37 ` Michal Hocko
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